An example of an event processing system which processes a large number of events generated in devices such as various sensors, RFID (Radio Frequency Identification) readers is described in Japanese Patent Publication No. 4161998. FIG. 32 shows a load distributing and dispatching system described in Japanese Patent Publication No. 4161998.
Referring to FIG. 32, the load distributing and dispatching system includes an event processing distributing unit 901, a context-independent dispatching unit 902, a plurality of context-dependent dispatching units (dispatchers) 903a and 903b (hereinafter, these are abbreviated as 903), and a plurality of event processing servers 904a and 904b (hereinafter, these are abbreviated as 904).
Applications 906a and 906b (hereinafter, these are abbreviated as 906) transmit an event processing rule to the event processing distributing unit 901 (arrow 911). The event processing distributing unit 901 sets the processing rule to one of the plurality of processing servers 904 (arrow 912). The event processing distributing unit 901 generates an event dispatching rule (dispatch rule) in such a way that an event processed according to the processing rule is transmitted to the processing server to which the processing rule is set, and sets the generated dispatch rule to the context-dependent dispatching units 903 (arrows 913a and 913b).
The context-independent dispatching unit 902, when receiving an event from a device, 905, such as any of devise 905a and device 905b, dispatches the event to the context-dependent dispatching units 903 at random (arrows 914a, 914b, 915a, and 915b). The context-dependent dispatching units 903, when receiving the event from the context-independent dispatching unit 902, dispatches the event to the event processing servers 904 to which the processing rule for the event is set based on the event dispatching rule that has been set (arrows 916a, 916b, 916c, and 916d). The event processing servers 904 processes the event based on the processing rule and notifies the applications 906 of an event processing result (arrows 917a and 917b).